Nunapitchuk, AK 99609 Frost Dates
99609, near Nunapitchuk, AK: the frost window
The last spring frost here typically falls around 05/21, about 266 days from today. Fall's first freeze usually shows up around 09/22, roughly 122 days after the last spring frost.
Nunapitchuk sits in USDA Zone 4a (-30 to -25°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Nunapitchuk's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/21 isn't a guarantee
05/21 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/02 and only about 1 year in 10 sees frost after that.
Nunapitchuk against the rest of the dataset
About 122 days separate Nunapitchuk's last and first frost, putting it 38,963 of 40,283 ZIP codes nationally. Within AK, it ranks 112 of 269.
Learn more
Two guides worth reading on 99609: local microclimates, on what one yard in Nunapitchuk can differ from the 99609 normal, and zone vs. frost date, on why Zone 4a and Nunapitchuk's frost date answer different questions.